Severe infections in patients with autoimmune diseases treated with cyclophosphamide

Infectious diseases are a significant cause of morbidity and mortality in patients with connective tissue diseases. Corticosteroids and immunosuppressive drugs, such as cyclophosphamide (CYC), increases the risk of infections. The objective of this study was to estimate the incidence rates of severe infections in patients who received treatment with CYC.

The records of 60 patients with systemic autoimmune diseases who received treatment with CYC were retrospectively reviewed. We evaluated the rate of severe infections that occurred during CYC therapy and the 3 subsequent months.

Systemic lupus erythematosus was the most common disease, and diffuse proliferative glomerulonephritis the most frequent indication. Severe infection occurred in 9 patients (15%). Community acquired pneumonia was the most frequent infection with 3 cases (33%) followed by Herpes Zoster with 2 reports (22%). The cumulative dose of corticosteroid was the only significant risk factor for infection 32.8±16.7 vs. 20.1±15.3 P=.007.

The use of lower doses of corticosteroids and an aggressive management of infectious complications, allows for an acceptable safety profile in patients treated with CYC.